Income Taxes

9 Months Ended

Sep. 30, 2012

Income Tax Disclosure [Abstract]

INCOME TAXES

INCOME TAXES

The Company's provision for income taxes in interim periods is based on an estimated annual effective income tax rate derived, in part, from estimated annual pre-tax results from ordinary operations. The annual effective income tax rate is reviewed and, if necessary, adjusted on a quarterly basis.

The Company's income tax expense consisted of the following:

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2012			2011			2012			2011
Income before provision for income taxes	$	31,234		$	30,000		$	25,180		$	110,868
Income tax expense using estimated annual effective income tax rate	12,024			11,920			9,694			44,051
Out-of-period adjustment related to non-deductible expenses in 2011	—			—			757			—
Impact of discrete item, net	(148		)	—			(808		)	464
Changes in effective tax rates	1,426			1,401			1,400			—
Reduction of valuation allowance	—			(870		)	—			(870		)
Income tax expense	$	13,302		$	12,451		$	11,043		$	43,645

The discrete item for the nine months ended September 30, 2012 and the three and nine months ended September 30, 2011, is related to the conversion of the Company's 3.875% Senior Convertible Debentures due 2026. The out-of-period adjustment related to a non-accrual of a non-deductible expense related to a permanent difference for income taxes in the fourth quarter of 2011. The Company assessed the materiality of this error on all previously issued financial statements and concluded that the error was immaterial to all previously issued financial statements. The impact of correcting this error in the current year is not expected to be material to the Company’s 2012 consolidated financial statements.

The Internal Revenue Service is auditing the Company's 2008 and 2009 tax years. The Company believes it has adequately reserved for any potential adjustments that may arise as a result of the audits.